af_packet.c 62.3 KB
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/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		PACKET - implements raw packet sockets.
 *
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 * Authors:	Ross Biro
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 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
 *
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 * Fixes:
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 *		Alan Cox	:	verify_area() now used correctly
 *		Alan Cox	:	new skbuff lists, look ma no backlogs!
 *		Alan Cox	:	tidied skbuff lists.
 *		Alan Cox	:	Now uses generic datagram routines I
 *					added. Also fixed the peek/read crash
 *					from all old Linux datagram code.
 *		Alan Cox	:	Uses the improved datagram code.
 *		Alan Cox	:	Added NULL's for socket options.
 *		Alan Cox	:	Re-commented the code.
 *		Alan Cox	:	Use new kernel side addressing
 *		Rob Janssen	:	Correct MTU usage.
 *		Dave Platt	:	Counter leaks caused by incorrect
 *					interrupt locking and some slightly
 *					dubious gcc output. Can you read
 *					compiler: it said _VOLATILE_
 *	Richard Kooijman	:	Timestamp fixes.
 *		Alan Cox	:	New buffers. Use sk->mac.raw.
 *		Alan Cox	:	sendmsg/recvmsg support.
 *		Alan Cox	:	Protocol setting support
 *	Alexey Kuznetsov	:	Untied from IPv4 stack.
 *	Cyrus Durgin		:	Fixed kerneld for kmod.
 *	Michal Ostrowski        :       Module initialization cleanup.
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 *         Ulises Alonso        :       Frame number limit removal and
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 *                                      packet_set_ring memory leak.
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 *		Eric Biederman	:	Allow for > 8 byte hardware addresses.
 *					The convention is that longer addresses
 *					will simply extend the hardware address
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 *					byte arrays at the end of sockaddr_ll
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 *					and packet_mreq.
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 *		Johann Baudy	:	Added TX RING.
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 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 */
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#include <linux/types.h>
#include <linux/mm.h>
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#include <linux/capability.h>
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#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/wireless.h>
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#include <linux/kernel.h>
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#include <linux/kmod.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <net/net_namespace.h>
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#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <asm/page.h>
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#include <asm/cacheflush.h>
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#include <asm/io.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/init.h>
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#include <linux/mutex.h>
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#include <linux/if_vlan.h>
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#include <linux/virtio_net.h>
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#include <linux/errqueue.h>
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#include <linux/net_tstamp.h>
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#ifdef CONFIG_INET
#include <net/inet_common.h>
#endif

/*
   Assumptions:
   - if device has no dev->hard_header routine, it adds and removes ll header
     inside itself. In this case ll header is invisible outside of device,
     but higher levels still should reserve dev->hard_header_len.
     Some devices are enough clever to reallocate skb, when header
     will not fit to reserved space (tunnel), another ones are silly
     (PPP).
   - packet socket receives packets with pulled ll header,
     so that SOCK_RAW should push it back.

On receive:
-----------

Incoming, dev->hard_header!=NULL
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   mac_header -> ll header
   data       -> data
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Outgoing, dev->hard_header!=NULL
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   mac_header -> ll header
   data       -> ll header
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Incoming, dev->hard_header==NULL
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   mac_header -> UNKNOWN position. It is very likely, that it points to ll
		 header.  PPP makes it, that is wrong, because introduce
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		 assymetry between rx and tx paths.
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   data       -> data
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Outgoing, dev->hard_header==NULL
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   mac_header -> data. ll header is still not built!
   data       -> data
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Resume
  If dev->hard_header==NULL we are unlikely to restore sensible ll header.


On transmit:
------------

dev->hard_header != NULL
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   mac_header -> ll header
   data       -> ll header
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dev->hard_header == NULL (ll header is added by device, we cannot control it)
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   mac_header -> data
   data       -> data
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   We should set nh.raw on output to correct posistion,
   packet classifier depends on it.
 */

/* Private packet socket structures. */

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struct packet_mclist {
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	struct packet_mclist	*next;
	int			ifindex;
	int			count;
	unsigned short		type;
	unsigned short		alen;
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	unsigned char		addr[MAX_ADDR_LEN];
};
/* identical to struct packet_mreq except it has
 * a longer address field.
 */
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struct packet_mreq_max {
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	int		mr_ifindex;
	unsigned short	mr_type;
	unsigned short	mr_alen;
	unsigned char	mr_address[MAX_ADDR_LEN];
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};
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static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
		int closing, int tx_ring);

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struct pgv {
	char *buffer;
};

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struct packet_ring_buffer {
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	struct pgv		*pg_vec;
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	unsigned int		head;
	unsigned int		frames_per_block;
	unsigned int		frame_size;
	unsigned int		frame_max;

	unsigned int		pg_vec_order;
	unsigned int		pg_vec_pages;
	unsigned int		pg_vec_len;

	atomic_t		pending;
};

struct packet_sock;
static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
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static void packet_flush_mclist(struct sock *sk);

struct packet_sock {
	/* struct sock has to be the first member of packet_sock */
	struct sock		sk;
	struct tpacket_stats	stats;
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	struct packet_ring_buffer	rx_ring;
	struct packet_ring_buffer	tx_ring;
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	int			copy_thresh;
	spinlock_t		bind_lock;
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	struct mutex		pg_vec_lock;
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	unsigned int		running:1,	/* prot_hook is attached*/
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				auxdata:1,
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				origdev:1,
				has_vnet_hdr:1;
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	int			ifindex;	/* bound device		*/
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	__be16			num;
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	struct packet_mclist	*mclist;
	atomic_t		mapped;
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	enum tpacket_versions	tp_version;
	unsigned int		tp_hdrlen;
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	unsigned int		tp_reserve;
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	unsigned int		tp_loss:1;
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	unsigned int		tp_tstamp;
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	struct packet_type	prot_hook ____cacheline_aligned_in_smp;
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};

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struct packet_skb_cb {
	unsigned int origlen;
	union {
		struct sockaddr_pkt pkt;
		struct sockaddr_ll ll;
	} sa;
};

#define PACKET_SKB_CB(__skb)	((struct packet_skb_cb *)((__skb)->cb))
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static inline __pure struct page *pgv_to_page(void *addr)
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{
	if (is_vmalloc_addr(addr))
		return vmalloc_to_page(addr);
	return virt_to_page(addr);
}

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static void __packet_set_status(struct packet_sock *po, void *frame, int status)
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{
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	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} h;
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	h.raw = frame;
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	switch (po->tp_version) {
	case TPACKET_V1:
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		h.h1->tp_status = status;
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		flush_dcache_page(pgv_to_page(&h.h1->tp_status));
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		break;
	case TPACKET_V2:
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		h.h2->tp_status = status;
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		flush_dcache_page(pgv_to_page(&h.h2->tp_status));
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		break;
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	default:
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		pr_err("TPACKET version not supported\n");
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		BUG();
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	}
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	smp_wmb();
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}

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static int __packet_get_status(struct packet_sock *po, void *frame)
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{
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} h;

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	smp_rmb();

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	h.raw = frame;
	switch (po->tp_version) {
	case TPACKET_V1:
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		flush_dcache_page(pgv_to_page(&h.h1->tp_status));
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		return h.h1->tp_status;
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	case TPACKET_V2:
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		flush_dcache_page(pgv_to_page(&h.h2->tp_status));
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		return h.h2->tp_status;
	default:
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		pr_err("TPACKET version not supported\n");
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		BUG();
		return 0;
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	}
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}
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static void *packet_lookup_frame(struct packet_sock *po,
		struct packet_ring_buffer *rb,
		unsigned int position,
		int status)
{
	unsigned int pg_vec_pos, frame_offset;
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} h;

	pg_vec_pos = position / rb->frames_per_block;
	frame_offset = position % rb->frames_per_block;

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	h.raw = rb->pg_vec[pg_vec_pos].buffer +
		(frame_offset * rb->frame_size);
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	if (status != __packet_get_status(po, h.raw))
		return NULL;

	return h.raw;
}

static inline void *packet_current_frame(struct packet_sock *po,
		struct packet_ring_buffer *rb,
		int status)
{
	return packet_lookup_frame(po, rb, rb->head, status);
}

static inline void *packet_previous_frame(struct packet_sock *po,
		struct packet_ring_buffer *rb,
		int status)
{
	unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
	return packet_lookup_frame(po, rb, previous, status);
}

static inline void packet_increment_head(struct packet_ring_buffer *buff)
{
	buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
}

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static inline struct packet_sock *pkt_sk(struct sock *sk)
{
	return (struct packet_sock *)sk;
}

static void packet_sock_destruct(struct sock *sk)
{
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	skb_queue_purge(&sk->sk_error_queue);

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	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
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	if (!sock_flag(sk, SOCK_DEAD)) {
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		pr_err("Attempt to release alive packet socket: %p\n", sk);
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		return;
	}

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	sk_refcnt_debug_dec(sk);
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}


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static const struct proto_ops packet_ops;
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static const struct proto_ops packet_ops_spkt;
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static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
			   struct packet_type *pt, struct net_device *orig_dev)
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{
	struct sock *sk;
	struct sockaddr_pkt *spkt;

	/*
	 *	When we registered the protocol we saved the socket in the data
	 *	field for just this event.
	 */

	sk = pt->af_packet_priv;
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	/*
	 *	Yank back the headers [hope the device set this
	 *	right or kerboom...]
	 *
	 *	Incoming packets have ll header pulled,
	 *	push it back.
	 *
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	 *	For outgoing ones skb->data == skb_mac_header(skb)
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	 *	so that this procedure is noop.
	 */

	if (skb->pkt_type == PACKET_LOOPBACK)
		goto out;

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	if (!net_eq(dev_net(dev), sock_net(sk)))
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		goto out;

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	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL)
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		goto oom;

	/* drop any routing info */
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	skb_dst_drop(skb);
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	/* drop conntrack reference */
	nf_reset(skb);

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	spkt = &PACKET_SKB_CB(skb)->sa.pkt;
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	skb_push(skb, skb->data - skb_mac_header(skb));
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	/*
	 *	The SOCK_PACKET socket receives _all_ frames.
	 */

	spkt->spkt_family = dev->type;
	strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
	spkt->spkt_protocol = skb->protocol;

	/*
	 *	Charge the memory to the socket. This is done specifically
	 *	to prevent sockets using all the memory up.
	 */

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	if (sock_queue_rcv_skb(sk, skb) == 0)
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		return 0;

out:
	kfree_skb(skb);
oom:
	return 0;
}


/*
 *	Output a raw packet to a device layer. This bypasses all the other
 *	protocol layers and you must therefore supply it with a complete frame
 */
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static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
			       struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
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	struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
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	struct sk_buff *skb = NULL;
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	struct net_device *dev;
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	__be16 proto = 0;
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	int err;
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	/*
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	 *	Get and verify the address.
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	 */

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	if (saddr) {
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		if (msg->msg_namelen < sizeof(struct sockaddr))
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			return -EINVAL;
		if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
			proto = saddr->spkt_protocol;
	} else
		return -ENOTCONN;	/* SOCK_PACKET must be sent giving an address */
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	/*
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	 *	Find the device first to size check it
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	 */

	saddr->spkt_device[13] = 0;
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retry:
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	rcu_read_lock();
	dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
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	err = -ENODEV;
	if (dev == NULL)
		goto out_unlock;
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	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

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	/*
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	 * You may not queue a frame bigger than the mtu. This is the lowest level
	 * raw protocol and you must do your own fragmentation at this level.
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	 */
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	err = -EMSGSIZE;
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	if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN)
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		goto out_unlock;

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	if (!skb) {
		size_t reserved = LL_RESERVED_SPACE(dev);
		unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;

		rcu_read_unlock();
		skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
		if (skb == NULL)
			return -ENOBUFS;
		/* FIXME: Save some space for broken drivers that write a hard
		 * header at transmission time by themselves. PPP is the notable
		 * one here. This should really be fixed at the driver level.
		 */
		skb_reserve(skb, reserved);
		skb_reset_network_header(skb);

		/* Try to align data part correctly */
		if (hhlen) {
			skb->data -= hhlen;
			skb->tail -= hhlen;
			if (len < hhlen)
				skb_reset_network_header(skb);
		}
		err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
		if (err)
			goto out_free;
		goto retry;
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	}

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	if (len > (dev->mtu + dev->hard_header_len)) {
		/* Earlier code assumed this would be a VLAN pkt,
		 * double-check this now that we have the actual
		 * packet in hand.
		 */
		struct ethhdr *ehdr;
		skb_reset_mac_header(skb);
		ehdr = eth_hdr(skb);
		if (ehdr->h_proto != htons(ETH_P_8021Q)) {
			err = -EMSGSIZE;
			goto out_unlock;
		}
	}
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	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
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	skb->mark = sk->sk_mark;
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	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
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	if (err < 0)
		goto out_unlock;
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	dev_queue_xmit(skb);
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	rcu_read_unlock();
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	return len;
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out_unlock:
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	rcu_read_unlock();
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out_free:
	kfree_skb(skb);
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	return err;
}

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static inline unsigned int run_filter(const struct sk_buff *skb,
				      const struct sock *sk,
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				      unsigned int res)
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{
	struct sk_filter *filter;
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	rcu_read_lock();
	filter = rcu_dereference(sk->sk_filter);
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	if (filter != NULL)
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		res = SK_RUN_FILTER(filter, skb);
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	rcu_read_unlock();
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	return res;
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}

/*
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 * This function makes lazy skb cloning in hope that most of packets
 * are discarded by BPF.
 *
 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
 * and skb->cb are mangled. It works because (and until) packets
 * falling here are owned by current CPU. Output packets are cloned
 * by dev_queue_xmit_nit(), input packets are processed by net_bh
 * sequencially, so that if we return skb to original state on exit,
 * we will not harm anyone.
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 */

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static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
		      struct packet_type *pt, struct net_device *orig_dev)
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{
	struct sock *sk;
	struct sockaddr_ll *sll;
	struct packet_sock *po;
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Eric Dumazet 已提交
565
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
566
	int skb_len = skb->len;
D
David S. Miller 已提交
567
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
568 569 570 571 572 573 574

	if (skb->pkt_type == PACKET_LOOPBACK)
		goto drop;

	sk = pt->af_packet_priv;
	po = pkt_sk(sk);

O
Octavian Purdila 已提交
575
	if (!net_eq(dev_net(dev), sock_net(sk)))
576 577
		goto drop;

L
Linus Torvalds 已提交
578 579
	skb->dev = dev;

580
	if (dev->header_ops) {
L
Linus Torvalds 已提交
581
		/* The device has an explicit notion of ll header,
E
Eric Dumazet 已提交
582 583 584 585 586
		 * exported to higher levels.
		 *
		 * Otherwise, the device hides details of its frame
		 * structure, so that corresponding packet head is
		 * never delivered to user.
L
Linus Torvalds 已提交
587 588
		 */
		if (sk->sk_type != SOCK_DGRAM)
589
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
590 591
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
592
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
593 594 595 596 597
		}
	}

	snaplen = skb->len;

D
David S. Miller 已提交
598 599
	res = run_filter(skb, sk, snaplen);
	if (!res)
600
		goto drop_n_restore;
D
David S. Miller 已提交
601 602
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620

	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
	    (unsigned)sk->sk_rcvbuf)
		goto drop_n_acct;

	if (skb_shared(skb)) {
		struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
		if (nskb == NULL)
			goto drop_n_acct;

		if (skb_head != skb->data) {
			skb->data = skb_head;
			skb->len = skb_len;
		}
		kfree_skb(skb);
		skb = nskb;
	}

621 622 623 624
	BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
		     sizeof(skb->cb));

	sll = &PACKET_SKB_CB(skb)->sa.ll;
L
Linus Torvalds 已提交
625 626 627 628
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
629
	if (unlikely(po->origdev))
630 631 632
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
633

S
Stephen Hemminger 已提交
634
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
635

636
	PACKET_SKB_CB(skb)->origlen = skb->len;
637

L
Linus Torvalds 已提交
638 639 640 641 642
	if (pskb_trim(skb, snaplen))
		goto drop_n_acct;

	skb_set_owner_r(skb, sk);
	skb->dev = NULL;
E
Eric Dumazet 已提交
643
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
644

645 646 647
	/* drop conntrack reference */
	nf_reset(skb);

L
Linus Torvalds 已提交
648 649
	spin_lock(&sk->sk_receive_queue.lock);
	po->stats.tp_packets++;
650
	skb->dropcount = atomic_read(&sk->sk_drops);
L
Linus Torvalds 已提交
651 652 653 654 655 656
	__skb_queue_tail(&sk->sk_receive_queue, skb);
	spin_unlock(&sk->sk_receive_queue.lock);
	sk->sk_data_ready(sk, skb->len);
	return 0;

drop_n_acct:
657
	po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);
L
Linus Torvalds 已提交
658 659 660 661 662 663 664

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
665
	consume_skb(skb);
L
Linus Torvalds 已提交
666 667 668
	return 0;
}

E
Eric Dumazet 已提交
669 670
static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
		       struct packet_type *pt, struct net_device *orig_dev)
L
Linus Torvalds 已提交
671 672 673 674
{
	struct sock *sk;
	struct packet_sock *po;
	struct sockaddr_ll *sll;
675 676 677 678 679
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} h;
E
Eric Dumazet 已提交
680
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
681
	int skb_len = skb->len;
D
David S. Miller 已提交
682
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
683
	unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
684
	unsigned short macoff, netoff, hdrlen;
L
Linus Torvalds 已提交
685
	struct sk_buff *copy_skb = NULL;
686
	struct timeval tv;
687
	struct timespec ts;
688
	struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
L
Linus Torvalds 已提交
689 690 691 692 693 694 695

	if (skb->pkt_type == PACKET_LOOPBACK)
		goto drop;

	sk = pt->af_packet_priv;
	po = pkt_sk(sk);

O
Octavian Purdila 已提交
696
	if (!net_eq(dev_net(dev), sock_net(sk)))
697 698
		goto drop;

699
	if (dev->header_ops) {
L
Linus Torvalds 已提交
700
		if (sk->sk_type != SOCK_DGRAM)
701
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
702 703
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
704
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
705 706 707
		}
	}

708 709 710
	if (skb->ip_summed == CHECKSUM_PARTIAL)
		status |= TP_STATUS_CSUMNOTREADY;

L
Linus Torvalds 已提交
711 712
	snaplen = skb->len;

D
David S. Miller 已提交
713 714
	res = run_filter(skb, sk, snaplen);
	if (!res)
715
		goto drop_n_restore;
D
David S. Miller 已提交
716 717
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
718 719

	if (sk->sk_type == SOCK_DGRAM) {
720 721
		macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
				  po->tp_reserve;
L
Linus Torvalds 已提交
722
	} else {
723
		unsigned maclen = skb_network_offset(skb);
724
		netoff = TPACKET_ALIGN(po->tp_hdrlen +
725 726
				       (maclen < 16 ? 16 : maclen)) +
			po->tp_reserve;
L
Linus Torvalds 已提交
727 728 729
		macoff = netoff - maclen;
	}

J
Johann Baudy 已提交
730
	if (macoff + snaplen > po->rx_ring.frame_size) {
L
Linus Torvalds 已提交
731 732 733 734 735 736 737 738 739 740 741 742
		if (po->copy_thresh &&
		    atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
		    (unsigned)sk->sk_rcvbuf) {
			if (skb_shared(skb)) {
				copy_skb = skb_clone(skb, GFP_ATOMIC);
			} else {
				copy_skb = skb_get(skb);
				skb_head = skb->data;
			}
			if (copy_skb)
				skb_set_owner_r(copy_skb, sk);
		}
J
Johann Baudy 已提交
743
		snaplen = po->rx_ring.frame_size - macoff;
L
Linus Torvalds 已提交
744 745 746 747 748
		if ((int)snaplen < 0)
			snaplen = 0;
	}

	spin_lock(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
749
	h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL);
750
	if (!h.raw)
L
Linus Torvalds 已提交
751
		goto ring_is_full;
J
Johann Baudy 已提交
752
	packet_increment_head(&po->rx_ring);
L
Linus Torvalds 已提交
753 754 755 756 757 758 759 760 761
	po->stats.tp_packets++;
	if (copy_skb) {
		status |= TP_STATUS_COPY;
		__skb_queue_tail(&sk->sk_receive_queue, copy_skb);
	}
	if (!po->stats.tp_drops)
		status &= ~TP_STATUS_LOSING;
	spin_unlock(&sk->sk_receive_queue.lock);

762
	skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
L
Linus Torvalds 已提交
763

764 765 766 767 768 769
	switch (po->tp_version) {
	case TPACKET_V1:
		h.h1->tp_len = skb->len;
		h.h1->tp_snaplen = snaplen;
		h.h1->tp_mac = macoff;
		h.h1->tp_net = netoff;
770 771 772 773 774 775 776
		if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
				&& shhwtstamps->syststamp.tv64)
			tv = ktime_to_timeval(shhwtstamps->syststamp);
		else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
				&& shhwtstamps->hwtstamp.tv64)
			tv = ktime_to_timeval(shhwtstamps->hwtstamp);
		else if (skb->tstamp.tv64)
777 778 779 780 781 782 783 784 785 786 787 788
			tv = ktime_to_timeval(skb->tstamp);
		else
			do_gettimeofday(&tv);
		h.h1->tp_sec = tv.tv_sec;
		h.h1->tp_usec = tv.tv_usec;
		hdrlen = sizeof(*h.h1);
		break;
	case TPACKET_V2:
		h.h2->tp_len = skb->len;
		h.h2->tp_snaplen = snaplen;
		h.h2->tp_mac = macoff;
		h.h2->tp_net = netoff;
789 790 791 792 793 794 795
		if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
				&& shhwtstamps->syststamp.tv64)
			ts = ktime_to_timespec(shhwtstamps->syststamp);
		else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
				&& shhwtstamps->hwtstamp.tv64)
			ts = ktime_to_timespec(shhwtstamps->hwtstamp);
		else if (skb->tstamp.tv64)
796 797 798 799 800
			ts = ktime_to_timespec(skb->tstamp);
		else
			getnstimeofday(&ts);
		h.h2->tp_sec = ts.tv_sec;
		h.h2->tp_nsec = ts.tv_nsec;
801 802 803 804 805 806
		if (vlan_tx_tag_present(skb)) {
			h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
			status |= TP_STATUS_VLAN_VALID;
		} else {
			h.h2->tp_vlan_tci = 0;
		}
807 808 809 810 811
		hdrlen = sizeof(*h.h2);
		break;
	default:
		BUG();
	}
L
Linus Torvalds 已提交
812

813
	sll = h.raw + TPACKET_ALIGN(hdrlen);
S
Stephen Hemminger 已提交
814
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
815 816 817 818
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
819
	if (unlikely(po->origdev))
820 821 822
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
823

824
	__packet_set_status(po, h.raw, status);
R
Ralf Baechle 已提交
825
	smp_mb();
826
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
L
Linus Torvalds 已提交
827
	{
828 829 830 831 832
		u8 *start, *end;

		end = (u8 *)PAGE_ALIGN((unsigned long)h.raw + macoff + snaplen);
		for (start = h.raw; start < end; start += PAGE_SIZE)
			flush_dcache_page(pgv_to_page(start));
L
Linus Torvalds 已提交
833
	}
834
#endif
L
Linus Torvalds 已提交
835 836 837 838 839 840 841 842 843

	sk->sk_data_ready(sk, 0);

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
844
	kfree_skb(skb);
L
Linus Torvalds 已提交
845 846 847 848 849 850 851
	return 0;

ring_is_full:
	po->stats.tp_drops++;
	spin_unlock(&sk->sk_receive_queue.lock);

	sk->sk_data_ready(sk, 0);
852
	kfree_skb(copy_skb);
L
Linus Torvalds 已提交
853 854 855
	goto drop_n_restore;
}

J
Johann Baudy 已提交
856 857 858
static void tpacket_destruct_skb(struct sk_buff *skb)
{
	struct packet_sock *po = pkt_sk(skb->sk);
E
Eric Dumazet 已提交
859
	void *ph;
L
Linus Torvalds 已提交
860

J
Johann Baudy 已提交
861
	BUG_ON(skb == NULL);
L
Linus Torvalds 已提交
862

J
Johann Baudy 已提交
863 864 865 866 867 868 869 870 871 872 873
	if (likely(po->tx_ring.pg_vec)) {
		ph = skb_shinfo(skb)->destructor_arg;
		BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
		BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
		atomic_dec(&po->tx_ring.pending);
		__packet_set_status(po, ph, TP_STATUS_AVAILABLE);
	}

	sock_wfree(skb);
}

E
Eric Dumazet 已提交
874 875 876
static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
		void *frame, struct net_device *dev, int size_max,
		__be16 proto, unsigned char *addr)
J
Johann Baudy 已提交
877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893
{
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} ph;
	int to_write, offset, len, tp_len, nr_frags, len_max;
	struct socket *sock = po->sk.sk_socket;
	struct page *page;
	void *data;
	int err;

	ph.raw = frame;

	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = po->sk.sk_priority;
894
	skb->mark = po->sk.sk_mark;
J
Johann Baudy 已提交
895 896 897 898 899 900 901 902 903 904 905
	skb_shinfo(skb)->destructor_arg = ph.raw;

	switch (po->tp_version) {
	case TPACKET_V2:
		tp_len = ph.h2->tp_len;
		break;
	default:
		tp_len = ph.h1->tp_len;
		break;
	}
	if (unlikely(tp_len > size_max)) {
E
Eric Dumazet 已提交
906
		pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
J
Johann Baudy 已提交
907 908 909 910 911 912 913 914 915 916 917 918 919 920
		return -EMSGSIZE;
	}

	skb_reserve(skb, LL_RESERVED_SPACE(dev));
	skb_reset_network_header(skb);

	data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
	to_write = tp_len;

	if (sock->type == SOCK_DGRAM) {
		err = dev_hard_header(skb, dev, ntohs(proto), addr,
				NULL, tp_len);
		if (unlikely(err < 0))
			return -EINVAL;
E
Eric Dumazet 已提交
921
	} else if (dev->hard_header_len) {
J
Johann Baudy 已提交
922 923
		/* net device doesn't like empty head */
		if (unlikely(tp_len <= dev->hard_header_len)) {
E
Eric Dumazet 已提交
924 925
			pr_err("packet size is too short (%d < %d)\n",
			       tp_len, dev->hard_header_len);
J
Johann Baudy 已提交
926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952
			return -EINVAL;
		}

		skb_push(skb, dev->hard_header_len);
		err = skb_store_bits(skb, 0, data,
				dev->hard_header_len);
		if (unlikely(err))
			return err;

		data += dev->hard_header_len;
		to_write -= dev->hard_header_len;
	}

	err = -EFAULT;
	offset = offset_in_page(data);
	len_max = PAGE_SIZE - offset;
	len = ((to_write > len_max) ? len_max : to_write);

	skb->data_len = to_write;
	skb->len += to_write;
	skb->truesize += to_write;
	atomic_add(to_write, &po->sk.sk_wmem_alloc);

	while (likely(to_write)) {
		nr_frags = skb_shinfo(skb)->nr_frags;

		if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
E
Eric Dumazet 已提交
953 954
			pr_err("Packet exceed the number of skb frags(%lu)\n",
			       MAX_SKB_FRAGS);
J
Johann Baudy 已提交
955 956 957
			return -EFAULT;
		}

958 959
		page = pgv_to_page(data);
		data += len;
J
Johann Baudy 已提交
960 961
		flush_dcache_page(page);
		get_page(page);
962
		skb_fill_page_desc(skb, nr_frags, page, offset, len);
J
Johann Baudy 已提交
963 964 965 966 967 968 969 970 971 972 973 974 975 976
		to_write -= len;
		offset = 0;
		len_max = PAGE_SIZE;
		len = ((to_write > len_max) ? len_max : to_write);
	}

	return tp_len;
}

static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
{
	struct sk_buff *skb;
	struct net_device *dev;
	__be16 proto;
977 978
	bool need_rls_dev = false;
	int err, reserve = 0;
E
Eric Dumazet 已提交
979 980
	void *ph;
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
J
Johann Baudy 已提交
981 982 983 984 985 986 987 988 989
	int tp_len, size_max;
	unsigned char *addr;
	int len_sum = 0;
	int status = 0;

	mutex_lock(&po->pg_vec_lock);

	err = -EBUSY;
	if (saddr == NULL) {
990
		dev = po->prot_hook.dev;
J
Johann Baudy 已提交
991 992 993 994 995 996 997 998 999 1000 1001 1002
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
		if (msg->msg_namelen < (saddr->sll_halen
					+ offsetof(struct sockaddr_ll,
						sll_addr)))
			goto out;
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
1003 1004
		dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
		need_rls_dev = true;
J
Johann Baudy 已提交
1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
	}

	err = -ENXIO;
	if (unlikely(dev == NULL))
		goto out;

	reserve = dev->hard_header_len;

	err = -ENETDOWN;
	if (unlikely(!(dev->flags & IFF_UP)))
		goto out_put;

	size_max = po->tx_ring.frame_size
1018
		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));
J
Johann Baudy 已提交
1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063

	if (size_max > dev->mtu + reserve)
		size_max = dev->mtu + reserve;

	do {
		ph = packet_current_frame(po, &po->tx_ring,
				TP_STATUS_SEND_REQUEST);

		if (unlikely(ph == NULL)) {
			schedule();
			continue;
		}

		status = TP_STATUS_SEND_REQUEST;
		skb = sock_alloc_send_skb(&po->sk,
				LL_ALLOCATED_SPACE(dev)
				+ sizeof(struct sockaddr_ll),
				0, &err);

		if (unlikely(skb == NULL))
			goto out_status;

		tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
				addr);

		if (unlikely(tp_len < 0)) {
			if (po->tp_loss) {
				__packet_set_status(po, ph,
						TP_STATUS_AVAILABLE);
				packet_increment_head(&po->tx_ring);
				kfree_skb(skb);
				continue;
			} else {
				status = TP_STATUS_WRONG_FORMAT;
				err = tp_len;
				goto out_status;
			}
		}

		skb->destructor = tpacket_destruct_skb;
		__packet_set_status(po, ph, TP_STATUS_SENDING);
		atomic_inc(&po->tx_ring.pending);

		status = TP_STATUS_SEND_REQUEST;
		err = dev_queue_xmit(skb);
1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077
		if (unlikely(err > 0)) {
			err = net_xmit_errno(err);
			if (err && __packet_get_status(po, ph) ==
				   TP_STATUS_AVAILABLE) {
				/* skb was destructed already */
				skb = NULL;
				goto out_status;
			}
			/*
			 * skb was dropped but not destructed yet;
			 * let's treat it like congestion or err < 0
			 */
			err = 0;
		}
J
Johann Baudy 已提交
1078 1079
		packet_increment_head(&po->tx_ring);
		len_sum += tp_len;
1080 1081 1082 1083
	} while (likely((ph != NULL) ||
			((!(msg->msg_flags & MSG_DONTWAIT)) &&
			 (atomic_read(&po->tx_ring.pending))))
		);
J
Johann Baudy 已提交
1084 1085 1086 1087 1088 1089 1090 1091

	err = len_sum;
	goto out_put;

out_status:
	__packet_set_status(po, ph, status);
	kfree_skb(skb);
out_put:
1092 1093
	if (need_rls_dev)
		dev_put(dev);
J
Johann Baudy 已提交
1094 1095 1096 1097 1098
out:
	mutex_unlock(&po->pg_vec_lock);
	return err;
}

1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122
static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
					       size_t reserve, size_t len,
					       size_t linear, int noblock,
					       int *err)
{
	struct sk_buff *skb;

	/* Under a page?  Don't bother with paged skb. */
	if (prepad + len < PAGE_SIZE || !linear)
		linear = len;

	skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
				   err);
	if (!skb)
		return NULL;

	skb_reserve(skb, reserve);
	skb_put(skb, linear);
	skb->data_len = len - linear;
	skb->len += len - linear;

	return skb;
}

J
Johann Baudy 已提交
1123
static int packet_snd(struct socket *sock,
L
Linus Torvalds 已提交
1124 1125 1126
			  struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
E
Eric Dumazet 已提交
1127
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
L
Linus Torvalds 已提交
1128 1129
	struct sk_buff *skb;
	struct net_device *dev;
A
Al Viro 已提交
1130
	__be16 proto;
1131
	bool need_rls_dev = false;
L
Linus Torvalds 已提交
1132
	unsigned char *addr;
1133
	int err, reserve = 0;
1134 1135 1136 1137 1138
	struct virtio_net_hdr vnet_hdr = { 0 };
	int offset = 0;
	int vnet_hdr_len;
	struct packet_sock *po = pkt_sk(sk);
	unsigned short gso_type = 0;
L
Linus Torvalds 已提交
1139 1140

	/*
1141
	 *	Get and verify the address.
L
Linus Torvalds 已提交
1142
	 */
1143

L
Linus Torvalds 已提交
1144
	if (saddr == NULL) {
1145
		dev = po->prot_hook.dev;
L
Linus Torvalds 已提交
1146 1147 1148 1149 1150 1151
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
1152 1153
		if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
			goto out;
L
Linus Torvalds 已提交
1154 1155
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
1156 1157
		dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
		need_rls_dev = true;
L
Linus Torvalds 已提交
1158 1159 1160 1161 1162 1163 1164 1165
	}

	err = -ENXIO;
	if (dev == NULL)
		goto out_unlock;
	if (sock->type == SOCK_RAW)
		reserve = dev->hard_header_len;

1166 1167 1168 1169
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217
	if (po->has_vnet_hdr) {
		vnet_hdr_len = sizeof(vnet_hdr);

		err = -EINVAL;
		if (len < vnet_hdr_len)
			goto out_unlock;

		len -= vnet_hdr_len;

		err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
				       vnet_hdr_len);
		if (err < 0)
			goto out_unlock;

		if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
		    (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
		      vnet_hdr.hdr_len))
			vnet_hdr.hdr_len = vnet_hdr.csum_start +
						 vnet_hdr.csum_offset + 2;

		err = -EINVAL;
		if (vnet_hdr.hdr_len > len)
			goto out_unlock;

		if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
			switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
			case VIRTIO_NET_HDR_GSO_TCPV4:
				gso_type = SKB_GSO_TCPV4;
				break;
			case VIRTIO_NET_HDR_GSO_TCPV6:
				gso_type = SKB_GSO_TCPV6;
				break;
			case VIRTIO_NET_HDR_GSO_UDP:
				gso_type = SKB_GSO_UDP;
				break;
			default:
				goto out_unlock;
			}

			if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
				gso_type |= SKB_GSO_TCP_ECN;

			if (vnet_hdr.gso_size == 0)
				goto out_unlock;

		}
	}

L
Linus Torvalds 已提交
1218
	err = -EMSGSIZE;
1219
	if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
L
Linus Torvalds 已提交
1220 1221
		goto out_unlock;

1222 1223 1224 1225
	err = -ENOBUFS;
	skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
			       LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
			       msg->msg_flags & MSG_DONTWAIT, &err);
E
Eric Dumazet 已提交
1226
	if (skb == NULL)
L
Linus Torvalds 已提交
1227 1228
		goto out_unlock;

1229
	skb_set_network_header(skb, reserve);
L
Linus Torvalds 已提交
1230

1231 1232
	err = -EINVAL;
	if (sock->type == SOCK_DGRAM &&
1233
	    (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
1234
		goto out_free;
L
Linus Torvalds 已提交
1235 1236

	/* Returns -EFAULT on error */
1237
	err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
L
Linus Torvalds 已提交
1238 1239
	if (err)
		goto out_free;
1240
	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1241 1242
	if (err < 0)
		goto out_free;
L
Linus Torvalds 已提交
1243

1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257
	if (!gso_type && (len > dev->mtu + reserve)) {
		/* Earlier code assumed this would be a VLAN pkt,
		 * double-check this now that we have the actual
		 * packet in hand.
		 */
		struct ethhdr *ehdr;
		skb_reset_mac_header(skb);
		ehdr = eth_hdr(skb);
		if (ehdr->h_proto != htons(ETH_P_8021Q)) {
			err = -EMSGSIZE;
			goto out_free;
		}
	}

L
Linus Torvalds 已提交
1258 1259 1260
	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
1261
	skb->mark = sk->sk_mark;
L
Linus Torvalds 已提交
1262

1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281
	if (po->has_vnet_hdr) {
		if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
			if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
						  vnet_hdr.csum_offset)) {
				err = -EINVAL;
				goto out_free;
			}
		}

		skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
		skb_shinfo(skb)->gso_type = gso_type;

		/* Header must be checked, and gso_segs computed. */
		skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
		skb_shinfo(skb)->gso_segs = 0;

		len += vnet_hdr_len;
	}

L
Linus Torvalds 已提交
1282 1283 1284 1285 1286 1287 1288 1289
	/*
	 *	Now send it
	 */

	err = dev_queue_xmit(skb);
	if (err > 0 && (err = net_xmit_errno(err)) != 0)
		goto out_unlock;

1290 1291
	if (need_rls_dev)
		dev_put(dev);
L
Linus Torvalds 已提交
1292

E
Eric Dumazet 已提交
1293
	return len;
L
Linus Torvalds 已提交
1294 1295 1296 1297

out_free:
	kfree_skb(skb);
out_unlock:
1298
	if (dev && need_rls_dev)
L
Linus Torvalds 已提交
1299 1300 1301 1302 1303
		dev_put(dev);
out:
	return err;
}

J
Johann Baudy 已提交
1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314
static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
		struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
	if (po->tx_ring.pg_vec)
		return tpacket_snd(po, msg);
	else
		return packet_snd(sock, msg, len);
}

L
Linus Torvalds 已提交
1315 1316 1317 1318 1319 1320 1321 1322 1323
/*
 *	Close a PACKET socket. This is fairly simple. We immediately go
 *	to 'closed' state and remove our protocol entry in the device list.
 */

static int packet_release(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct packet_sock *po;
1324
	struct net *net;
J
Johann Baudy 已提交
1325
	struct tpacket_req req;
L
Linus Torvalds 已提交
1326 1327 1328 1329

	if (!sk)
		return 0;

1330
	net = sock_net(sk);
L
Linus Torvalds 已提交
1331 1332
	po = pkt_sk(sk);

1333 1334
	spin_lock_bh(&net->packet.sklist_lock);
	sk_del_node_init_rcu(sk);
1335
	sock_prot_inuse_add(net, sk->sk_prot, -1);
1336
	spin_unlock_bh(&net->packet.sklist_lock);
L
Linus Torvalds 已提交
1337

1338
	spin_lock(&po->bind_lock);
L
Linus Torvalds 已提交
1339 1340
	if (po->running) {
		/*
1341
		 * Remove from protocol table
L
Linus Torvalds 已提交
1342 1343 1344
		 */
		po->running = 0;
		po->num = 0;
1345
		__dev_remove_pack(&po->prot_hook);
L
Linus Torvalds 已提交
1346 1347
		__sock_put(sk);
	}
1348 1349 1350 1351
	if (po->prot_hook.dev) {
		dev_put(po->prot_hook.dev);
		po->prot_hook.dev = NULL;
	}
1352
	spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
1353 1354 1355

	packet_flush_mclist(sk);

J
Johann Baudy 已提交
1356 1357 1358 1359 1360 1361 1362
	memset(&req, 0, sizeof(req));

	if (po->rx_ring.pg_vec)
		packet_set_ring(sk, &req, 1, 0);

	if (po->tx_ring.pg_vec)
		packet_set_ring(sk, &req, 1, 1);
L
Linus Torvalds 已提交
1363

1364
	synchronize_net();
L
Linus Torvalds 已提交
1365 1366 1367 1368 1369 1370 1371 1372 1373
	/*
	 *	Now the socket is dead. No more input will appear.
	 */
	sock_orphan(sk);
	sock->sk = NULL;

	/* Purge queues */

	skb_queue_purge(&sk->sk_receive_queue);
1374
	sk_refcnt_debug_release(sk);
L
Linus Torvalds 已提交
1375 1376 1377 1378 1379 1380 1381 1382 1383

	sock_put(sk);
	return 0;
}

/*
 *	Attach a packet hook.
 */

A
Al Viro 已提交
1384
static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
L
Linus Torvalds 已提交
1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404
{
	struct packet_sock *po = pkt_sk(sk);
	/*
	 *	Detach an existing hook if present.
	 */

	lock_sock(sk);

	spin_lock(&po->bind_lock);
	if (po->running) {
		__sock_put(sk);
		po->running = 0;
		po->num = 0;
		spin_unlock(&po->bind_lock);
		dev_remove_pack(&po->prot_hook);
		spin_lock(&po->bind_lock);
	}

	po->num = protocol;
	po->prot_hook.type = protocol;
1405 1406
	if (po->prot_hook.dev)
		dev_put(po->prot_hook.dev);
L
Linus Torvalds 已提交
1407 1408 1409 1410 1411 1412 1413
	po->prot_hook.dev = dev;

	po->ifindex = dev ? dev->ifindex : 0;

	if (protocol == 0)
		goto out_unlock;

1414
	if (!dev || (dev->flags & IFF_UP)) {
L
Linus Torvalds 已提交
1415 1416 1417
		dev_add_pack(&po->prot_hook);
		sock_hold(sk);
		po->running = 1;
1418 1419 1420 1421
	} else {
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
L
Linus Torvalds 已提交
1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433
	}

out_unlock:
	spin_unlock(&po->bind_lock);
	release_sock(sk);
	return 0;
}

/*
 *	Bind a packet socket to a device
 */

E
Eric Dumazet 已提交
1434 1435
static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
			    int addr_len)
L
Linus Torvalds 已提交
1436
{
E
Eric Dumazet 已提交
1437
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
1438 1439 1440
	char name[15];
	struct net_device *dev;
	int err = -ENODEV;
1441

L
Linus Torvalds 已提交
1442 1443 1444
	/*
	 *	Check legality
	 */
1445

1446
	if (addr_len != sizeof(struct sockaddr))
L
Linus Torvalds 已提交
1447
		return -EINVAL;
E
Eric Dumazet 已提交
1448
	strlcpy(name, uaddr->sa_data, sizeof(name));
L
Linus Torvalds 已提交
1449

1450
	dev = dev_get_by_name(sock_net(sk), name);
1451
	if (dev)
L
Linus Torvalds 已提交
1452 1453 1454 1455 1456 1457
		err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
	return err;
}

static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
E
Eric Dumazet 已提交
1458 1459
	struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
1460 1461 1462 1463 1464 1465 1466
	struct net_device *dev = NULL;
	int err;


	/*
	 *	Check legality
	 */
1467

L
Linus Torvalds 已提交
1468 1469 1470 1471 1472 1473 1474
	if (addr_len < sizeof(struct sockaddr_ll))
		return -EINVAL;
	if (sll->sll_family != AF_PACKET)
		return -EINVAL;

	if (sll->sll_ifindex) {
		err = -ENODEV;
1475
		dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
L
Linus Torvalds 已提交
1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491
		if (dev == NULL)
			goto out;
	}
	err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);

out:
	return err;
}

static struct proto packet_proto = {
	.name	  = "PACKET",
	.owner	  = THIS_MODULE,
	.obj_size = sizeof(struct packet_sock),
};

/*
1492
 *	Create a packet of type SOCK_PACKET.
L
Linus Torvalds 已提交
1493 1494
 */

1495 1496
static int packet_create(struct net *net, struct socket *sock, int protocol,
			 int kern)
L
Linus Torvalds 已提交
1497 1498 1499
{
	struct sock *sk;
	struct packet_sock *po;
A
Al Viro 已提交
1500
	__be16 proto = (__force __be16)protocol; /* weird, but documented */
L
Linus Torvalds 已提交
1501 1502 1503 1504
	int err;

	if (!capable(CAP_NET_RAW))
		return -EPERM;
1505 1506
	if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
	    sock->type != SOCK_PACKET)
L
Linus Torvalds 已提交
1507 1508 1509 1510 1511
		return -ESOCKTNOSUPPORT;

	sock->state = SS_UNCONNECTED;

	err = -ENOBUFS;
1512
	sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
L
Linus Torvalds 已提交
1513 1514 1515 1516 1517 1518
	if (sk == NULL)
		goto out;

	sock->ops = &packet_ops;
	if (sock->type == SOCK_PACKET)
		sock->ops = &packet_ops_spkt;
1519

L
Linus Torvalds 已提交
1520 1521 1522 1523
	sock_init_data(sock, sk);

	po = pkt_sk(sk);
	sk->sk_family = PF_PACKET;
A
Al Viro 已提交
1524
	po->num = proto;
L
Linus Torvalds 已提交
1525 1526

	sk->sk_destruct = packet_sock_destruct;
1527
	sk_refcnt_debug_inc(sk);
L
Linus Torvalds 已提交
1528 1529 1530 1531 1532 1533

	/*
	 *	Attach a protocol block
	 */

	spin_lock_init(&po->bind_lock);
1534
	mutex_init(&po->pg_vec_lock);
L
Linus Torvalds 已提交
1535
	po->prot_hook.func = packet_rcv;
1536

L
Linus Torvalds 已提交
1537 1538
	if (sock->type == SOCK_PACKET)
		po->prot_hook.func = packet_rcv_spkt;
1539

L
Linus Torvalds 已提交
1540 1541
	po->prot_hook.af_packet_priv = sk;

A
Al Viro 已提交
1542 1543
	if (proto) {
		po->prot_hook.type = proto;
L
Linus Torvalds 已提交
1544 1545 1546 1547 1548
		dev_add_pack(&po->prot_hook);
		sock_hold(sk);
		po->running = 1;
	}

1549 1550
	spin_lock_bh(&net->packet.sklist_lock);
	sk_add_node_rcu(sk, &net->packet.sklist);
1551
	sock_prot_inuse_add(net, &packet_proto, 1);
1552 1553
	spin_unlock_bh(&net->packet.sklist_lock);

E
Eric Dumazet 已提交
1554
	return 0;
L
Linus Torvalds 已提交
1555 1556 1557 1558
out:
	return err;
}

1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603
static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
{
	struct sock_exterr_skb *serr;
	struct sk_buff *skb, *skb2;
	int copied, err;

	err = -EAGAIN;
	skb = skb_dequeue(&sk->sk_error_queue);
	if (skb == NULL)
		goto out;

	copied = skb->len;
	if (copied > len) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free_skb;

	sock_recv_timestamp(msg, sk, skb);

	serr = SKB_EXT_ERR(skb);
	put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
		 sizeof(serr->ee), &serr->ee);

	msg->msg_flags |= MSG_ERRQUEUE;
	err = copied;

	/* Reset and regenerate socket error */
	spin_lock_bh(&sk->sk_error_queue.lock);
	sk->sk_err = 0;
	if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
		spin_unlock_bh(&sk->sk_error_queue.lock);
		sk->sk_error_report(sk);
	} else
		spin_unlock_bh(&sk->sk_error_queue.lock);

out_free_skb:
	kfree_skb(skb);
out:
	return err;
}

L
Linus Torvalds 已提交
1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614
/*
 *	Pull a packet from our receive queue and hand it to the user.
 *	If necessary we block.
 */

static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
			  struct msghdr *msg, size_t len, int flags)
{
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	int copied, err;
1615
	struct sockaddr_ll *sll;
1616
	int vnet_hdr_len = 0;
L
Linus Torvalds 已提交
1617 1618

	err = -EINVAL;
1619
	if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
L
Linus Torvalds 已提交
1620 1621 1622 1623 1624 1625 1626 1627
		goto out;

#if 0
	/* What error should we return now? EUNATTACH? */
	if (pkt_sk(sk)->ifindex < 0)
		return -ENODEV;
#endif

1628 1629 1630 1631 1632
	if (flags & MSG_ERRQUEUE) {
		err = packet_recv_error(sk, msg, len);
		goto out;
	}

L
Linus Torvalds 已提交
1633 1634 1635 1636 1637 1638 1639 1640 1641
	/*
	 *	Call the generic datagram receiver. This handles all sorts
	 *	of horrible races and re-entrancy so we can forget about it
	 *	in the protocol layers.
	 *
	 *	Now it will return ENETDOWN, if device have just gone down,
	 *	but then it will block.
	 */

E
Eric Dumazet 已提交
1642
	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
L
Linus Torvalds 已提交
1643 1644

	/*
1645
	 *	An error occurred so return it. Because skb_recv_datagram()
L
Linus Torvalds 已提交
1646 1647 1648 1649
	 *	handles the blocking we don't see and worry about blocking
	 *	retries.
	 */

1650
	if (skb == NULL)
L
Linus Torvalds 已提交
1651 1652
		goto out;

1653 1654 1655 1656 1657
	if (pkt_sk(sk)->has_vnet_hdr) {
		struct virtio_net_hdr vnet_hdr = { 0 };

		err = -EINVAL;
		vnet_hdr_len = sizeof(vnet_hdr);
1658
		if (len < vnet_hdr_len)
1659 1660
			goto out_free;

1661 1662
		len -= vnet_hdr_len;

1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685
		if (skb_is_gso(skb)) {
			struct skb_shared_info *sinfo = skb_shinfo(skb);

			/* This is a hint as to how much should be linear. */
			vnet_hdr.hdr_len = skb_headlen(skb);
			vnet_hdr.gso_size = sinfo->gso_size;
			if (sinfo->gso_type & SKB_GSO_TCPV4)
				vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
			else if (sinfo->gso_type & SKB_GSO_TCPV6)
				vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
			else if (sinfo->gso_type & SKB_GSO_UDP)
				vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
			else if (sinfo->gso_type & SKB_GSO_FCOE)
				goto out_free;
			else
				BUG();
			if (sinfo->gso_type & SKB_GSO_TCP_ECN)
				vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
		} else
			vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;

		if (skb->ip_summed == CHECKSUM_PARTIAL) {
			vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
1686
			vnet_hdr.csum_start = skb_checksum_start_offset(skb);
1687 1688 1689 1690 1691 1692 1693 1694 1695
			vnet_hdr.csum_offset = skb->csum_offset;
		} /* else everything is zero */

		err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
				     vnet_hdr_len);
		if (err < 0)
			goto out_free;
	}

1696 1697 1698 1699 1700
	/*
	 *	If the address length field is there to be filled in, we fill
	 *	it in now.
	 */

1701
	sll = &PACKET_SKB_CB(skb)->sa.ll;
1702 1703 1704 1705 1706
	if (sock->type == SOCK_PACKET)
		msg->msg_namelen = sizeof(struct sockaddr_pkt);
	else
		msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);

L
Linus Torvalds 已提交
1707 1708 1709 1710 1711 1712
	/*
	 *	You lose any data beyond the buffer you gave. If it worries a
	 *	user program they can ask the device for its MTU anyway.
	 */

	copied = skb->len;
E
Eric Dumazet 已提交
1713 1714 1715
	if (copied > len) {
		copied = len;
		msg->msg_flags |= MSG_TRUNC;
L
Linus Torvalds 已提交
1716 1717 1718 1719 1720 1721
	}

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free;

1722
	sock_recv_ts_and_drops(msg, sk, skb);
L
Linus Torvalds 已提交
1723 1724

	if (msg->msg_name)
1725 1726
		memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
		       msg->msg_namelen);
L
Linus Torvalds 已提交
1727

1728
	if (pkt_sk(sk)->auxdata) {
1729 1730 1731 1732 1733 1734 1735 1736
		struct tpacket_auxdata aux;

		aux.tp_status = TP_STATUS_USER;
		if (skb->ip_summed == CHECKSUM_PARTIAL)
			aux.tp_status |= TP_STATUS_CSUMNOTREADY;
		aux.tp_len = PACKET_SKB_CB(skb)->origlen;
		aux.tp_snaplen = skb->len;
		aux.tp_mac = 0;
1737
		aux.tp_net = skb_network_offset(skb);
1738 1739 1740 1741 1742 1743
		if (vlan_tx_tag_present(skb)) {
			aux.tp_vlan_tci = vlan_tx_tag_get(skb);
			aux.tp_status |= TP_STATUS_VLAN_VALID;
		} else {
			aux.tp_vlan_tci = 0;
		}
1744
		put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1745 1746
	}

L
Linus Torvalds 已提交
1747 1748 1749 1750
	/*
	 *	Free or return the buffer as appropriate. Again this
	 *	hides all the races and re-entrancy issues from us.
	 */
1751
	err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
L
Linus Torvalds 已提交
1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768

out_free:
	skb_free_datagram(sk, skb);
out:
	return err;
}

static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
			       int *uaddr_len, int peer)
{
	struct net_device *dev;
	struct sock *sk	= sock->sk;

	if (peer)
		return -EOPNOTSUPP;

	uaddr->sa_family = AF_PACKET;
E
Eric Dumazet 已提交
1769 1770 1771
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
	if (dev)
1772
		strncpy(uaddr->sa_data, dev->name, 14);
E
Eric Dumazet 已提交
1773
	else
L
Linus Torvalds 已提交
1774
		memset(uaddr->sa_data, 0, 14);
E
Eric Dumazet 已提交
1775
	rcu_read_unlock();
L
Linus Torvalds 已提交
1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786
	*uaddr_len = sizeof(*uaddr);

	return 0;
}

static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
			  int *uaddr_len, int peer)
{
	struct net_device *dev;
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
1787
	DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
L
Linus Torvalds 已提交
1788 1789 1790 1791 1792 1793 1794

	if (peer)
		return -EOPNOTSUPP;

	sll->sll_family = AF_PACKET;
	sll->sll_ifindex = po->ifindex;
	sll->sll_protocol = po->num;
1795
	sll->sll_pkttype = 0;
E
Eric Dumazet 已提交
1796 1797
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
L
Linus Torvalds 已提交
1798 1799 1800 1801 1802 1803 1804 1805
	if (dev) {
		sll->sll_hatype = dev->type;
		sll->sll_halen = dev->addr_len;
		memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
	} else {
		sll->sll_hatype = 0;	/* Bad: we have no ARPHRD_UNSPEC */
		sll->sll_halen = 0;
	}
E
Eric Dumazet 已提交
1806
	rcu_read_unlock();
1807
	*uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
L
Linus Torvalds 已提交
1808 1809 1810 1811

	return 0;
}

1812 1813
static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
			 int what)
L
Linus Torvalds 已提交
1814 1815 1816
{
	switch (i->type) {
	case PACKET_MR_MULTICAST:
1817 1818
		if (i->alen != dev->addr_len)
			return -EINVAL;
L
Linus Torvalds 已提交
1819
		if (what > 0)
1820
			return dev_mc_add(dev, i->addr);
L
Linus Torvalds 已提交
1821
		else
1822
			return dev_mc_del(dev, i->addr);
L
Linus Torvalds 已提交
1823 1824
		break;
	case PACKET_MR_PROMISC:
1825
		return dev_set_promiscuity(dev, what);
L
Linus Torvalds 已提交
1826 1827
		break;
	case PACKET_MR_ALLMULTI:
1828
		return dev_set_allmulti(dev, what);
L
Linus Torvalds 已提交
1829
		break;
1830
	case PACKET_MR_UNICAST:
1831 1832
		if (i->alen != dev->addr_len)
			return -EINVAL;
1833
		if (what > 0)
1834
			return dev_uc_add(dev, i->addr);
1835
		else
1836
			return dev_uc_del(dev, i->addr);
1837
		break;
E
Eric Dumazet 已提交
1838 1839
	default:
		break;
L
Linus Torvalds 已提交
1840
	}
1841
	return 0;
L
Linus Torvalds 已提交
1842 1843 1844 1845
}

static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
{
E
Eric Dumazet 已提交
1846
	for ( ; i; i = i->next) {
L
Linus Torvalds 已提交
1847 1848 1849 1850 1851
		if (i->ifindex == dev->ifindex)
			packet_dev_mc(dev, i, what);
	}
}

1852
static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
1853 1854 1855 1856 1857 1858 1859 1860 1861
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml, *i;
	struct net_device *dev;
	int err;

	rtnl_lock();

	err = -ENODEV;
1862
	dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
L
Linus Torvalds 已提交
1863 1864 1865 1866
	if (!dev)
		goto done;

	err = -EINVAL;
1867
	if (mreq->mr_alen > dev->addr_len)
L
Linus Torvalds 已提交
1868 1869 1870
		goto done;

	err = -ENOBUFS;
1871
	i = kmalloc(sizeof(*i), GFP_KERNEL);
L
Linus Torvalds 已提交
1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894
	if (i == NULL)
		goto done;

	err = 0;
	for (ml = po->mclist; ml; ml = ml->next) {
		if (ml->ifindex == mreq->mr_ifindex &&
		    ml->type == mreq->mr_type &&
		    ml->alen == mreq->mr_alen &&
		    memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
			ml->count++;
			/* Free the new element ... */
			kfree(i);
			goto done;
		}
	}

	i->type = mreq->mr_type;
	i->ifindex = mreq->mr_ifindex;
	i->alen = mreq->mr_alen;
	memcpy(i->addr, mreq->mr_address, i->alen);
	i->count = 1;
	i->next = po->mclist;
	po->mclist = i;
1895 1896 1897 1898 1899
	err = packet_dev_mc(dev, i, 1);
	if (err) {
		po->mclist = i->next;
		kfree(i);
	}
L
Linus Torvalds 已提交
1900 1901 1902 1903 1904 1905

done:
	rtnl_unlock();
	return err;
}

1906
static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919
{
	struct packet_mclist *ml, **mlp;

	rtnl_lock();

	for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
		if (ml->ifindex == mreq->mr_ifindex &&
		    ml->type == mreq->mr_type &&
		    ml->alen == mreq->mr_alen &&
		    memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
			if (--ml->count == 0) {
				struct net_device *dev;
				*mlp = ml->next;
1920 1921
				dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
				if (dev)
L
Linus Torvalds 已提交
1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945
					packet_dev_mc(dev, ml, -1);
				kfree(ml);
			}
			rtnl_unlock();
			return 0;
		}
	}
	rtnl_unlock();
	return -EADDRNOTAVAIL;
}

static void packet_flush_mclist(struct sock *sk)
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml;

	if (!po->mclist)
		return;

	rtnl_lock();
	while ((ml = po->mclist) != NULL) {
		struct net_device *dev;

		po->mclist = ml->next;
1946 1947
		dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
		if (dev != NULL)
L
Linus Torvalds 已提交
1948 1949 1950 1951 1952 1953 1954
			packet_dev_mc(dev, ml, -1);
		kfree(ml);
	}
	rtnl_unlock();
}

static int
1955
packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
1956 1957
{
	struct sock *sk = sock->sk;
1958
	struct packet_sock *po = pkt_sk(sk);
L
Linus Torvalds 已提交
1959 1960 1961 1962 1963
	int ret;

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

J
Johann Baudy 已提交
1964
	switch (optname) {
1965
	case PACKET_ADD_MEMBERSHIP:
L
Linus Torvalds 已提交
1966 1967
	case PACKET_DROP_MEMBERSHIP:
	{
1968 1969 1970 1971
		struct packet_mreq_max mreq;
		int len = optlen;
		memset(&mreq, 0, sizeof(mreq));
		if (len < sizeof(struct packet_mreq))
L
Linus Torvalds 已提交
1972
			return -EINVAL;
1973 1974
		if (len > sizeof(mreq))
			len = sizeof(mreq);
E
Eric Dumazet 已提交
1975
		if (copy_from_user(&mreq, optval, len))
L
Linus Torvalds 已提交
1976
			return -EFAULT;
1977 1978
		if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
			return -EINVAL;
L
Linus Torvalds 已提交
1979 1980 1981 1982 1983 1984
		if (optname == PACKET_ADD_MEMBERSHIP)
			ret = packet_mc_add(sk, &mreq);
		else
			ret = packet_mc_drop(sk, &mreq);
		return ret;
	}
1985

L
Linus Torvalds 已提交
1986
	case PACKET_RX_RING:
J
Johann Baudy 已提交
1987
	case PACKET_TX_RING:
L
Linus Torvalds 已提交
1988 1989 1990
	{
		struct tpacket_req req;

E
Eric Dumazet 已提交
1991
		if (optlen < sizeof(req))
L
Linus Torvalds 已提交
1992
			return -EINVAL;
1993 1994
		if (pkt_sk(sk)->has_vnet_hdr)
			return -EINVAL;
E
Eric Dumazet 已提交
1995
		if (copy_from_user(&req, optval, sizeof(req)))
L
Linus Torvalds 已提交
1996
			return -EFAULT;
J
Johann Baudy 已提交
1997
		return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
L
Linus Torvalds 已提交
1998 1999 2000 2001 2002
	}
	case PACKET_COPY_THRESH:
	{
		int val;

E
Eric Dumazet 已提交
2003
		if (optlen != sizeof(val))
L
Linus Torvalds 已提交
2004
			return -EINVAL;
E
Eric Dumazet 已提交
2005
		if (copy_from_user(&val, optval, sizeof(val)))
L
Linus Torvalds 已提交
2006 2007 2008 2009 2010
			return -EFAULT;

		pkt_sk(sk)->copy_thresh = val;
		return 0;
	}
2011 2012 2013 2014 2015 2016
	case PACKET_VERSION:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
2017
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
		case TPACKET_V2:
			po->tp_version = val;
			return 0;
		default:
			return -EINVAL;
		}
	}
2030 2031 2032 2033 2034 2035
	case PACKET_RESERVE:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
2036
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2037 2038 2039 2040 2041 2042
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_reserve = val;
		return 0;
	}
J
Johann Baudy 已提交
2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055
	case PACKET_LOSS:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_loss = !!val;
		return 0;
	}
2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067
	case PACKET_AUXDATA:
	{
		int val;

		if (optlen < sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->auxdata = !!val;
		return 0;
	}
2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079
	case PACKET_ORIGDEV:
	{
		int val;

		if (optlen < sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->origdev = !!val;
		return 0;
	}
2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095
	case PACKET_VNET_HDR:
	{
		int val;

		if (sock->type != SOCK_RAW)
			return -EINVAL;
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
			return -EBUSY;
		if (optlen < sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->has_vnet_hdr = !!val;
		return 0;
	}
2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107
	case PACKET_TIMESTAMP:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->tp_tstamp = val;
		return 0;
	}
L
Linus Torvalds 已提交
2108 2109 2110 2111 2112 2113 2114 2115 2116
	default:
		return -ENOPROTOOPT;
	}
}

static int packet_getsockopt(struct socket *sock, int level, int optname,
			     char __user *optval, int __user *optlen)
{
	int len;
2117
	int val;
L
Linus Torvalds 已提交
2118 2119
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
2120 2121
	void *data;
	struct tpacket_stats st;
L
Linus Torvalds 已提交
2122 2123 2124 2125

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

2126 2127
	if (get_user(len, optlen))
		return -EFAULT;
L
Linus Torvalds 已提交
2128 2129 2130

	if (len < 0)
		return -EINVAL;
2131

J
Johann Baudy 已提交
2132
	switch (optname) {
L
Linus Torvalds 已提交
2133 2134 2135 2136 2137 2138 2139 2140 2141
	case PACKET_STATISTICS:
		if (len > sizeof(struct tpacket_stats))
			len = sizeof(struct tpacket_stats);
		spin_lock_bh(&sk->sk_receive_queue.lock);
		st = po->stats;
		memset(&po->stats, 0, sizeof(st));
		spin_unlock_bh(&sk->sk_receive_queue.lock);
		st.tp_packets += st.tp_drops;

2142 2143 2144 2145 2146 2147 2148
		data = &st;
		break;
	case PACKET_AUXDATA:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->auxdata;

2149 2150 2151 2152 2153 2154 2155
		data = &val;
		break;
	case PACKET_ORIGDEV:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->origdev;

2156 2157 2158 2159 2160 2161 2162
		data = &val;
		break;
	case PACKET_VNET_HDR:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->has_vnet_hdr;

2163
		data = &val;
L
Linus Torvalds 已提交
2164
		break;
2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187
	case PACKET_VERSION:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->tp_version;
		data = &val;
		break;
	case PACKET_HDRLEN:
		if (len > sizeof(int))
			len = sizeof(int);
		if (copy_from_user(&val, optval, len))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
			val = sizeof(struct tpacket_hdr);
			break;
		case TPACKET_V2:
			val = sizeof(struct tpacket2_hdr);
			break;
		default:
			return -EINVAL;
		}
		data = &val;
		break;
2188 2189 2190 2191 2192 2193
	case PACKET_RESERVE:
		if (len > sizeof(unsigned int))
			len = sizeof(unsigned int);
		val = po->tp_reserve;
		data = &val;
		break;
J
Johann Baudy 已提交
2194 2195 2196 2197 2198 2199
	case PACKET_LOSS:
		if (len > sizeof(unsigned int))
			len = sizeof(unsigned int);
		val = po->tp_loss;
		data = &val;
		break;
2200 2201 2202 2203 2204 2205
	case PACKET_TIMESTAMP:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->tp_tstamp;
		data = &val;
		break;
L
Linus Torvalds 已提交
2206 2207 2208 2209
	default:
		return -ENOPROTOOPT;
	}

2210 2211
	if (put_user(len, optlen))
		return -EFAULT;
2212 2213
	if (copy_to_user(optval, data, len))
		return -EFAULT;
2214
	return 0;
L
Linus Torvalds 已提交
2215 2216 2217 2218 2219 2220 2221
}


static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
{
	struct sock *sk;
	struct hlist_node *node;
2222
	struct net_device *dev = data;
2223
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
2224

2225 2226
	rcu_read_lock();
	sk_for_each_rcu(sk, node, &net->packet.sklist) {
L
Linus Torvalds 已提交
2227 2228 2229 2230 2231 2232
		struct packet_sock *po = pkt_sk(sk);

		switch (msg) {
		case NETDEV_UNREGISTER:
			if (po->mclist)
				packet_dev_mclist(dev, po->mclist, -1);
2233 2234
			/* fallthrough */

L
Linus Torvalds 已提交
2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247
		case NETDEV_DOWN:
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
				if (po->running) {
					__dev_remove_pack(&po->prot_hook);
					__sock_put(sk);
					po->running = 0;
					sk->sk_err = ENETDOWN;
					if (!sock_flag(sk, SOCK_DEAD))
						sk->sk_error_report(sk);
				}
				if (msg == NETDEV_UNREGISTER) {
					po->ifindex = -1;
2248 2249
					if (po->prot_hook.dev)
						dev_put(po->prot_hook.dev);
L
Linus Torvalds 已提交
2250 2251 2252 2253 2254 2255
					po->prot_hook.dev = NULL;
				}
				spin_unlock(&po->bind_lock);
			}
			break;
		case NETDEV_UP:
2256 2257 2258 2259 2260 2261 2262 2263
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
				if (po->num && !po->running) {
					dev_add_pack(&po->prot_hook);
					sock_hold(sk);
					po->running = 1;
				}
				spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
2264 2265 2266 2267
			}
			break;
		}
	}
2268
	rcu_read_unlock();
L
Linus Torvalds 已提交
2269 2270 2271 2272 2273 2274 2275 2276 2277
	return NOTIFY_DONE;
}


static int packet_ioctl(struct socket *sock, unsigned int cmd,
			unsigned long arg)
{
	struct sock *sk = sock->sk;

J
Johann Baudy 已提交
2278
	switch (cmd) {
E
Eric Dumazet 已提交
2279 2280 2281
	case SIOCOUTQ:
	{
		int amount = sk_wmem_alloc_get(sk);
2282

E
Eric Dumazet 已提交
2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300
		return put_user(amount, (int __user *)arg);
	}
	case SIOCINQ:
	{
		struct sk_buff *skb;
		int amount = 0;

		spin_lock_bh(&sk->sk_receive_queue.lock);
		skb = skb_peek(&sk->sk_receive_queue);
		if (skb)
			amount = skb->len;
		spin_unlock_bh(&sk->sk_receive_queue.lock);
		return put_user(amount, (int __user *)arg);
	}
	case SIOCGSTAMP:
		return sock_get_timestamp(sk, (struct timeval __user *)arg);
	case SIOCGSTAMPNS:
		return sock_get_timestampns(sk, (struct timespec __user *)arg);
2301

L
Linus Torvalds 已提交
2302
#ifdef CONFIG_INET
E
Eric Dumazet 已提交
2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317
	case SIOCADDRT:
	case SIOCDELRT:
	case SIOCDARP:
	case SIOCGARP:
	case SIOCSARP:
	case SIOCGIFADDR:
	case SIOCSIFADDR:
	case SIOCGIFBRDADDR:
	case SIOCSIFBRDADDR:
	case SIOCGIFNETMASK:
	case SIOCSIFNETMASK:
	case SIOCGIFDSTADDR:
	case SIOCSIFDSTADDR:
	case SIOCSIFFLAGS:
		return inet_dgram_ops.ioctl(sock, cmd, arg);
L
Linus Torvalds 已提交
2318 2319
#endif

E
Eric Dumazet 已提交
2320 2321
	default:
		return -ENOIOCTLCMD;
L
Linus Torvalds 已提交
2322 2323 2324 2325
	}
	return 0;
}

E
Eric Dumazet 已提交
2326
static unsigned int packet_poll(struct file *file, struct socket *sock,
L
Linus Torvalds 已提交
2327 2328 2329 2330 2331 2332 2333
				poll_table *wait)
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
	unsigned int mask = datagram_poll(file, sock, wait);

	spin_lock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
2334 2335
	if (po->rx_ring.pg_vec) {
		if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL))
L
Linus Torvalds 已提交
2336 2337 2338
			mask |= POLLIN | POLLRDNORM;
	}
	spin_unlock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
2339 2340 2341 2342 2343 2344
	spin_lock_bh(&sk->sk_write_queue.lock);
	if (po->tx_ring.pg_vec) {
		if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
			mask |= POLLOUT | POLLWRNORM;
	}
	spin_unlock_bh(&sk->sk_write_queue.lock);
L
Linus Torvalds 已提交
2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355
	return mask;
}


/* Dirty? Well, I still did not learn better way to account
 * for user mmaps.
 */

static void packet_mm_open(struct vm_area_struct *vma)
{
	struct file *file = vma->vm_file;
E
Eric Dumazet 已提交
2356
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
2357
	struct sock *sk = sock->sk;
2358

L
Linus Torvalds 已提交
2359 2360 2361 2362 2363 2364 2365
	if (sk)
		atomic_inc(&pkt_sk(sk)->mapped);
}

static void packet_mm_close(struct vm_area_struct *vma)
{
	struct file *file = vma->vm_file;
E
Eric Dumazet 已提交
2366
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
2367
	struct sock *sk = sock->sk;
2368

L
Linus Torvalds 已提交
2369 2370 2371 2372
	if (sk)
		atomic_dec(&pkt_sk(sk)->mapped);
}

2373
static const struct vm_operations_struct packet_mmap_ops = {
E
Eric Dumazet 已提交
2374 2375
	.open	=	packet_mm_open,
	.close	=	packet_mm_close,
L
Linus Torvalds 已提交
2376 2377
};

2378 2379
static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
			unsigned int len)
L
Linus Torvalds 已提交
2380 2381 2382
{
	int i;

2383
	for (i = 0; i < len; i++) {
2384
		if (likely(pg_vec[i].buffer)) {
C
Changli Gao 已提交
2385
			if (is_vmalloc_addr(pg_vec[i].buffer))
2386 2387 2388 2389 2390 2391
				vfree(pg_vec[i].buffer);
			else
				free_pages((unsigned long)pg_vec[i].buffer,
					   order);
			pg_vec[i].buffer = NULL;
		}
L
Linus Torvalds 已提交
2392 2393 2394 2395
	}
	kfree(pg_vec);
}

C
Changli Gao 已提交
2396
static inline char *alloc_one_pg_vec_page(unsigned long order)
2397
{
2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409
	char *buffer = NULL;
	gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
			  __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;

	buffer = (char *) __get_free_pages(gfp_flags, order);

	if (buffer)
		return buffer;

	/*
	 * __get_free_pages failed, fall back to vmalloc
	 */
E
Eric Dumazet 已提交
2410
	buffer = vzalloc((1 << order) * PAGE_SIZE);
2411

2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426
	if (buffer)
		return buffer;

	/*
	 * vmalloc failed, lets dig into swap here
	 */
	gfp_flags &= ~__GFP_NORETRY;
	buffer = (char *)__get_free_pages(gfp_flags, order);
	if (buffer)
		return buffer;

	/*
	 * complete and utter failure
	 */
	return NULL;
2427 2428
}

2429
static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
2430 2431
{
	unsigned int block_nr = req->tp_block_nr;
2432
	struct pgv *pg_vec;
2433 2434
	int i;

2435
	pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
2436 2437 2438 2439
	if (unlikely(!pg_vec))
		goto out;

	for (i = 0; i < block_nr; i++) {
C
Changli Gao 已提交
2440
		pg_vec[i].buffer = alloc_one_pg_vec_page(order);
2441
		if (unlikely(!pg_vec[i].buffer))
2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452
			goto out_free_pgvec;
	}

out:
	return pg_vec;

out_free_pgvec:
	free_pg_vec(pg_vec, order, block_nr);
	pg_vec = NULL;
	goto out;
}
L
Linus Torvalds 已提交
2453

J
Johann Baudy 已提交
2454 2455
static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
		int closing, int tx_ring)
L
Linus Torvalds 已提交
2456
{
2457
	struct pgv *pg_vec = NULL;
L
Linus Torvalds 已提交
2458
	struct packet_sock *po = pkt_sk(sk);
A
Al Viro 已提交
2459
	int was_running, order = 0;
J
Johann Baudy 已提交
2460 2461
	struct packet_ring_buffer *rb;
	struct sk_buff_head *rb_queue;
A
Al Viro 已提交
2462
	__be16 num;
J
Johann Baudy 已提交
2463
	int err;
2464

J
Johann Baudy 已提交
2465 2466
	rb = tx_ring ? &po->tx_ring : &po->rx_ring;
	rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
L
Linus Torvalds 已提交
2467

J
Johann Baudy 已提交
2468 2469 2470 2471 2472 2473 2474
	err = -EBUSY;
	if (!closing) {
		if (atomic_read(&po->mapped))
			goto out;
		if (atomic_read(&rb->pending))
			goto out;
	}
L
Linus Torvalds 已提交
2475

J
Johann Baudy 已提交
2476 2477 2478 2479 2480
	if (req->tp_block_nr) {
		/* Sanity tests and some calculations */
		err = -EBUSY;
		if (unlikely(rb->pg_vec))
			goto out;
L
Linus Torvalds 已提交
2481

2482 2483 2484 2485 2486 2487 2488 2489 2490
		switch (po->tp_version) {
		case TPACKET_V1:
			po->tp_hdrlen = TPACKET_HDRLEN;
			break;
		case TPACKET_V2:
			po->tp_hdrlen = TPACKET2_HDRLEN;
			break;
		}

J
Johann Baudy 已提交
2491
		err = -EINVAL;
2492
		if (unlikely((int)req->tp_block_size <= 0))
J
Johann Baudy 已提交
2493
			goto out;
2494
		if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
J
Johann Baudy 已提交
2495
			goto out;
2496
		if (unlikely(req->tp_frame_size < po->tp_hdrlen +
J
Johann Baudy 已提交
2497 2498
					po->tp_reserve))
			goto out;
2499
		if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
J
Johann Baudy 已提交
2500
			goto out;
L
Linus Torvalds 已提交
2501

J
Johann Baudy 已提交
2502 2503 2504 2505 2506 2507
		rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
		if (unlikely(rb->frames_per_block <= 0))
			goto out;
		if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
					req->tp_frame_nr))
			goto out;
L
Linus Torvalds 已提交
2508 2509

		err = -ENOMEM;
2510 2511 2512
		order = get_order(req->tp_block_size);
		pg_vec = alloc_pg_vec(req, order);
		if (unlikely(!pg_vec))
L
Linus Torvalds 已提交
2513
			goto out;
J
Johann Baudy 已提交
2514 2515 2516 2517
	}
	/* Done */
	else {
		err = -EINVAL;
2518
		if (unlikely(req->tp_frame_nr))
J
Johann Baudy 已提交
2519
			goto out;
L
Linus Torvalds 已提交
2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534
	}

	lock_sock(sk);

	/* Detach socket from network */
	spin_lock(&po->bind_lock);
	was_running = po->running;
	num = po->num;
	if (was_running) {
		__dev_remove_pack(&po->prot_hook);
		po->num = 0;
		po->running = 0;
		__sock_put(sk);
	}
	spin_unlock(&po->bind_lock);
2535

L
Linus Torvalds 已提交
2536 2537 2538
	synchronize_net();

	err = -EBUSY;
2539
	mutex_lock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2540 2541
	if (closing || atomic_read(&po->mapped) == 0) {
		err = 0;
J
Johann Baudy 已提交
2542
		spin_lock_bh(&rb_queue->lock);
2543
		swap(rb->pg_vec, pg_vec);
J
Johann Baudy 已提交
2544 2545 2546 2547 2548
		rb->frame_max = (req->tp_frame_nr - 1);
		rb->head = 0;
		rb->frame_size = req->tp_frame_size;
		spin_unlock_bh(&rb_queue->lock);

2549 2550
		swap(rb->pg_vec_order, order);
		swap(rb->pg_vec_len, req->tp_block_nr);
J
Johann Baudy 已提交
2551 2552 2553 2554 2555

		rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
		po->prot_hook.func = (po->rx_ring.pg_vec) ?
						tpacket_rcv : packet_rcv;
		skb_queue_purge(rb_queue);
L
Linus Torvalds 已提交
2556
		if (atomic_read(&po->mapped))
E
Eric Dumazet 已提交
2557 2558
			pr_err("packet_mmap: vma is busy: %d\n",
			       atomic_read(&po->mapped));
L
Linus Torvalds 已提交
2559
	}
2560
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578

	spin_lock(&po->bind_lock);
	if (was_running && !po->running) {
		sock_hold(sk);
		po->running = 1;
		po->num = num;
		dev_add_pack(&po->prot_hook);
	}
	spin_unlock(&po->bind_lock);

	release_sock(sk);

	if (pg_vec)
		free_pg_vec(pg_vec, order, req->tp_block_nr);
out:
	return err;
}

J
Johann Baudy 已提交
2579 2580
static int packet_mmap(struct file *file, struct socket *sock,
		struct vm_area_struct *vma)
L
Linus Torvalds 已提交
2581 2582 2583
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
J
Johann Baudy 已提交
2584 2585
	unsigned long size, expected_size;
	struct packet_ring_buffer *rb;
L
Linus Torvalds 已提交
2586 2587 2588 2589 2590 2591 2592
	unsigned long start;
	int err = -EINVAL;
	int i;

	if (vma->vm_pgoff)
		return -EINVAL;

2593
	mutex_lock(&po->pg_vec_lock);
J
Johann Baudy 已提交
2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604

	expected_size = 0;
	for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
		if (rb->pg_vec) {
			expected_size += rb->pg_vec_len
						* rb->pg_vec_pages
						* PAGE_SIZE;
		}
	}

	if (expected_size == 0)
L
Linus Torvalds 已提交
2605
		goto out;
J
Johann Baudy 已提交
2606 2607 2608

	size = vma->vm_end - vma->vm_start;
	if (size != expected_size)
L
Linus Torvalds 已提交
2609 2610 2611
		goto out;

	start = vma->vm_start;
J
Johann Baudy 已提交
2612 2613 2614 2615 2616
	for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
		if (rb->pg_vec == NULL)
			continue;

		for (i = 0; i < rb->pg_vec_len; i++) {
2617 2618
			struct page *page;
			void *kaddr = rb->pg_vec[i].buffer;
J
Johann Baudy 已提交
2619 2620
			int pg_num;

C
Changli Gao 已提交
2621 2622
			for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
				page = pgv_to_page(kaddr);
J
Johann Baudy 已提交
2623 2624 2625 2626
				err = vm_insert_page(vma, start, page);
				if (unlikely(err))
					goto out;
				start += PAGE_SIZE;
2627
				kaddr += PAGE_SIZE;
J
Johann Baudy 已提交
2628
			}
2629
		}
L
Linus Torvalds 已提交
2630
	}
J
Johann Baudy 已提交
2631

2632
	atomic_inc(&po->mapped);
L
Linus Torvalds 已提交
2633 2634 2635 2636
	vma->vm_ops = &packet_mmap_ops;
	err = 0;

out:
2637
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2638 2639 2640
	return err;
}

2641
static const struct proto_ops packet_ops_spkt = {
L
Linus Torvalds 已提交
2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind_spkt,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
	.getname =	packet_getname_spkt,
	.poll =		datagram_poll,
	.ioctl =	packet_ioctl,
	.listen =	sock_no_listen,
	.shutdown =	sock_no_shutdown,
	.setsockopt =	sock_no_setsockopt,
	.getsockopt =	sock_no_getsockopt,
	.sendmsg =	packet_sendmsg_spkt,
	.recvmsg =	packet_recvmsg,
	.mmap =		sock_no_mmap,
	.sendpage =	sock_no_sendpage,
};

2662
static const struct proto_ops packet_ops = {
L
Linus Torvalds 已提交
2663 2664 2665 2666 2667 2668 2669
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
2670
	.getname =	packet_getname,
L
Linus Torvalds 已提交
2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682
	.poll =		packet_poll,
	.ioctl =	packet_ioctl,
	.listen =	sock_no_listen,
	.shutdown =	sock_no_shutdown,
	.setsockopt =	packet_setsockopt,
	.getsockopt =	packet_getsockopt,
	.sendmsg =	packet_sendmsg,
	.recvmsg =	packet_recvmsg,
	.mmap =		packet_mmap,
	.sendpage =	sock_no_sendpage,
};

2683
static const struct net_proto_family packet_family_ops = {
L
Linus Torvalds 已提交
2684 2685 2686 2687 2688 2689
	.family =	PF_PACKET,
	.create =	packet_create,
	.owner	=	THIS_MODULE,
};

static struct notifier_block packet_netdev_notifier = {
E
Eric Dumazet 已提交
2690
	.notifier_call =	packet_notifier,
L
Linus Torvalds 已提交
2691 2692 2693 2694 2695
};

#ifdef CONFIG_PROC_FS

static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2696
	__acquires(RCU)
L
Linus Torvalds 已提交
2697
{
2698
	struct net *net = seq_file_net(seq);
2699 2700 2701

	rcu_read_lock();
	return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
L
Linus Torvalds 已提交
2702 2703 2704 2705
}

static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
2706
	struct net *net = seq_file_net(seq);
2707
	return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
L
Linus Torvalds 已提交
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}

static void packet_seq_stop(struct seq_file *seq, void *v)
2711
	__releases(RCU)
L
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2712
{
2713
	rcu_read_unlock();
L
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2714 2715
}

2716
static int packet_seq_show(struct seq_file *seq, void *v)
L
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{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
	else {
2721
		struct sock *s = sk_entry(v);
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2722 2723 2724
		const struct packet_sock *po = pkt_sk(s);

		seq_printf(seq,
D
Dan Rosenberg 已提交
2725
			   "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
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			   s,
			   atomic_read(&s->sk_refcnt),
			   s->sk_type,
			   ntohs(po->num),
			   po->ifindex,
			   po->running,
			   atomic_read(&s->sk_rmem_alloc),
			   sock_i_uid(s),
E
Eric Dumazet 已提交
2734
			   sock_i_ino(s));
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	}

	return 0;
}

2740
static const struct seq_operations packet_seq_ops = {
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	.start	= packet_seq_start,
	.next	= packet_seq_next,
	.stop	= packet_seq_stop,
	.show	= packet_seq_show,
};

static int packet_seq_open(struct inode *inode, struct file *file)
{
2749 2750
	return seq_open_net(inode, file, &packet_seq_ops,
			    sizeof(struct seq_net_private));
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}

2753
static const struct file_operations packet_seq_fops = {
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	.owner		= THIS_MODULE,
	.open		= packet_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
2758
	.release	= seq_release_net,
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};

#endif

2763
static int __net_init packet_net_init(struct net *net)
2764
{
2765
	spin_lock_init(&net->packet.sklist_lock);
2766
	INIT_HLIST_HEAD(&net->packet.sklist);
2767 2768 2769 2770 2771 2772 2773

	if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
		return -ENOMEM;

	return 0;
}

2774
static void __net_exit packet_net_exit(struct net *net)
2775 2776 2777 2778 2779 2780 2781 2782 2783 2784
{
	proc_net_remove(net, "packet");
}

static struct pernet_operations packet_net_ops = {
	.init = packet_net_init,
	.exit = packet_net_exit,
};


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static void __exit packet_exit(void)
{
	unregister_netdevice_notifier(&packet_netdev_notifier);
2788
	unregister_pernet_subsys(&packet_net_ops);
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	sock_unregister(PF_PACKET);
	proto_unregister(&packet_proto);
}

static int __init packet_init(void)
{
	int rc = proto_register(&packet_proto, 0);

	if (rc != 0)
		goto out;

	sock_register(&packet_family_ops);
2801
	register_pernet_subsys(&packet_net_ops);
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	register_netdevice_notifier(&packet_netdev_notifier);
out:
	return rc;
}

module_init(packet_init);
module_exit(packet_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_PACKET);